Development of Real Estate Portal

I want to develop a real estate portal on which the available properties are displayed in a Google Maps window. When dragging the map in the map window the properties located in the new map window shall update and be displayed.

Next to the map window further details to (all) the properties shown in the map shall be displayed. This list shall be updated whenthe map window is dragged.

To give you an idea what I have in mind check: www.leerstandsmelder.de (I would like a different design and a few additional features as described below)

Additional features:

- search/filter function: user shall be able to insert a city name/post code in a box, which will result in the map centering on that city and all properties located in that area being displayed. Filters for property value, etc.

- when moving the cursor over a property in the map window, a little extra-window shall pop up displaying some details to that property and showing a link to a page where all details are displayed;

- when moving the cursor over a particular propertyin the list, that property shall be highlighted in the map window

- user registration/login for advanced features

- (registered) user shall be able to save interesting properties and make notes to it

The properties will be administered in a PostgreSQL database. I just require programming of the web-interface. The database can be accessed either directly  from the web-interface, or via webservice. But in this point I am open for suggestions.

I am looking forward to receive your quotes and time estimate for the realisation of this project.

G